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Thursday, September 15, 2011

Meconium

I've done a post on vernix, and one on the "ring of fire," among other useful things to know about childbirth that you may not know about, and now its time to do a post all about meconium!

Meconium is the first poo of a newborn. It is thick, sticky, brown and sometimes dark greenish. It is made up of what the baby was ingesting inside mom's uterus (like water, amniotic fluid, cells, vernix, etc) and is pretty sterile. It usually passes after the first couple days of the infant's life, turning into the more liquidy poop of a milk-fed baby.

If you're going to be a parent, you'll be seeing a lot of this!

I also just learned this interesting information:

The term meconium derives from ancient Greek meconium-arion, or "opium-like." Aristotle developed the term because he believed that it induced fetal sleep.

I've been asked a couple times about whether the baby poops or pees inside the uterus before being born. The answer is generally "no," but also "sometimes."

Occasionally, the meconium will be present in the amniotic fluid when the membranes rupture (a.k.a. when the water breaks). About 15-20% of babies are born with meconium in the fluid among term-pregnancies, and is increased to 30-40% among post-date pregnancies.

There are a few reasons why this would occur:

1. Women who are truly post-dates are more likely to have a baby that has "meconium-ed" in-utero. This is because their digestive system and bowels have reached maturity and started working.
2. Cord or head is being compressed during labor, which can cause heart rate decelerations, and is a normal physiological response and can happen without fetal distress.
3. True fetal distress. One theory is that the baby either isn't getting oxygen (hypoxia) or is stressed for another reason and poops in response.

Fetal distress can be present without meconium, and meconium can be present without fetal distress. The best indicator of fetal distress is abnormal heart rate, especially if coupled with meconium, and especially if the meconium is thick rather than thin.

Unfortunately, any presence of meconium in the amniotic fluid is cause for alarm among hospital staff. If meconium is discovered in the fluids, the laboring woman will be confined to labor attached to the monitors, with her movement restricted, which reduces her ability to move with her contractions to help the baby down through the pelvis and also restricts her ability to walk or use the shower for comfort. A time limit is also placed on the labor, and the risk of augmentation, c-section, or instruments to speed along the birth are increased. Once the baby is born, the cord will be immediately clamped and the baby will be whisked away from mom, rather than placed on her chest, to be vigorously suctioned.

The suctioning is done for fear of meconium aspiration. Meconium aspiration is when the baby inhales her own meconium, which is extremely rare but can be fatal. It is unlikely that the baby will inhale meconium in utero, unless the baby is extremely hypoxic, in which case they are gasping for air and might inhale their own stool. So, once again, meconium alone may not be a problem, but an oxygen-deprived baby showing other signs of distress may have a problem.

So, if this newborn poo during labor and birth is such a cause for concern, don't you think that care givers would do everything they could to reduce this occurrence? Unfortunately, in the U.S. at least, they do not. It is common practice to do procedures that have been scientifically shown to increase the chance of hypoxia, fetal distress, and meconium aspiration syndrome. For example, (via Midwife Thinking blog):

Inducing labour if the waters have broken (with meconium present) and there are no contractions or if labour is ‘slow’ in an attempt to get the baby out of the uterus quickly.

Performing an ARM (breaking the waters) to see if there is meconium in the waters when there are concerns about the fetal heart rate.

Creating concern and stress in the mother which can reduce the blood flow to the placenta.

Having extra people in the room (paediatricians), bright lights and medical resus equipment which may stress the mother and reduce oxytocin release.

Cutting the umbilical cord before the placenta has finished supporting the transition to breathing in order to hand the baby to the paediatrician.

To reduce chances for complications from meconium, try to avoid the above. For more suggestions on what to do when there is meconium in the amniotic fluid during labor, click over to the post linked above! She has even more information about how the airways are cleared during vaginal birth as the baby is squeezed through the birth canal!

The biggest piece of advice I would give is to avoid artificial rupture of membranes early on in labor unless there are other serious indications of fetal distress. Once meconium is discovered, the whole birth plan changes, even if the baby is doing fine!